Applicant claims priority from U.K. patent application 9906991.6 filed Mar. 25, 1999.
One type of coaxial switch assembly includes a switch with a pair of contacts, with one contact having a resilient beam portion that can be depressed out of engagement with the other contact. The contact element of a connector plug can be pressed down against the beam to deflect it out of engagement with the second contact while establishing electrical connection with the beam and therefore with the first contact. The switch generally has a housing with an entrance into which the connector plug is inserted. For a coaxial switch and plug, the entrance area is electrically conductive to electrically engage the outer contact element of the plug while the inner contact element deflects and engages the beam.
The center contact element of the plug often must project considerably down through an opening to downwardly deflect the beam, resulting in a plug with a long thin center contact element that is subject to damage. A switch assembly that avoided the need for such a protruding long and thin contact element, would avoid damage to such contact element.
When a coax plug is inserted into a coax switch, with the outer contact element of the plug engaging conductive walls of the entrance of the switch, previous systems require accurate alignment of the axis of the plug with the axis of the switch entrance. It would be desirable if good connection between the outer plug contact and the walls of the switch entrance could be established when the plug is pushed down to a final position, despite many degrees of misalignment of the plug with the switch.
In accordance with one embodiment of the present invention, a switch assembly is provided which enables a plug with a conductive plug element to open a switch by deflecting a beam, without requiring a long thin projecting plug element, and for use with a coaxial connector plug without requiring close alignment of the axis of the plug with that of switch. An upward projection on the resilient beam, projects at least partially through an opening of the switch, so the plug element can depress the projection and therefore not have to extend through and far below the opening to directly engage the beam.
The switch has walls forming a tapered entrance leading to the opening, to guide the plug into position. The walls of the entrance are electrically conductive to engage an outer coaxial contact element of the plug. This occurs while the inner coaxial contact element electrically connects to the beam through the projection, which is conductive. The front end of the outer coaxial element is of largely spherical shape, to provide a ring-shaped contact area despite many degrees of misalignment of the axis of the plug with the axis of the entrance.
The novel features of the invention are set forth with particularity in the appended claims. The invention will be best understood from the following description when read in conjunction with the accompanying drawings.